It is known that consumers desire to use cosmetic and personal care compositions that enhance the appearance of keratin fibers such as hair by changing the color of the hair and/or by imparting various properties to hair such as shine and conditioning. The process of changing the color of hair can involve either depositing an artificial color onto the hair which provides a different shade or color to the hair or lifting the color of the hair, such as for example, from a dark brown shade to a medium brown or a light brown shade.
Conventional hair coloring products include permanent hair dyeing products, also known as oxidation dyeing, which use the combination of compositions containing oxidative dye precursors, also known as primary intermediates or oxidation bases, and oxidizing products containing oxidizing agents such as peroxide and persulfate compounds, under alkaline pH conditions in the vast majority of cases. In general, the oxidation dye precursors comprise oxidation bases chosen from ortho- or para-phenylenediamines, ortho- or para-aminophenols, and heterocyclic compounds. These oxidation bases are colorless or weakly colored compounds, which, when combined with oxidizing products, can give access to colored species via a process of oxidative condensation.
The shades obtained with these oxidation bases may often be varied by combining them with at least one coupler, these couplers being chosen, for example, from aromatic meta-diamines, meta-aminophenols, meta-diphenols, and certain heterocyclic compounds, such as indole compounds. The variety of molecules used as oxidation bases and couplers can allow a wide range of colors to be obtained.
The oxidizing agent employed in permanent dyeing compositions may degrade the melanin of the hair, which, depending on the nature of the oxidizing agent present, may lead to less pronounced lightening of the fibers. Thus, for relatively weak lightening, the at least one oxidizing agent may be, for example, hydrogen peroxide. When more substantial lightening is desired, peroxygenated salts, such as persulfates, may be used in the presence of hydrogen peroxide.
Hair coloring compositions typically contain an alkalizing agent such as aqueous ammonia, not only for activating the oxidizing agent but also to cause the hair shaft to swell, thus allowing the small oxidative dye molecules to penetrate the cuticle and cortex before the oxidation condensation process is completed. The resulting larger-sized colored complexes from the oxidative reaction are then trapped inside the hair fiber, thereby permanently altering the color of the hair. However, the use of alkalizing agents, particularly, ammonia may affect the user, not only because of the undesirable odor of ammonia, but because alkalizing agents may also pose greater risks of intolerance, for instance, irritation of the scalp and stinging and may cause more degradation of the hair fibers.
The option of oxidatively dyeing hair in an acidic medium wherein all or part of the alkalizing agent is replaced by an acidifying agent has been explored. However, acidic dyeing systems may not be as efficient as alkalizing dyeing systems with respect to the degree of color deposit and intensity of color provided and with coloration time.
Thus, there is a need in the art for improved and/or alternate dyeing processes performed in the presence of at least one oxidizing agent, which do not have at least one of the drawbacks of the existing processes.
Thus, in order to improve the performance of such hair coloring compositions, the use of new and additional ingredients and novel combinations of ingredients are continuously sought; however, the choice of ingredients could pose difficulties insofar as they must improve the dyeing/lifting capability of the composition without being detrimental to other properties of the composition such as its application, rheology or viscosity properties, stability and/or resulting into more disadvantages such as increased damage or a less healthy look to the hair.
It is also important to provide hair coloring compositions with various types of consistency, such that the compositions can be provided in the form of a liquid emulsion, such as a liquid-lotion, liquid-gel, liquid-cream, or a cream emulsion, such as a thick cream or gel-cream, or a foam or mousse wherein the liquid emulsion form has a thinner consistency than the cream emulsion form and is typically packaged in a bottle. The liquid emulsion form is generally employed when the entire head of hair is to be colored or when only one color is desired since the dye composition spreads easily, allowing for greater coverage while the cream emulsion form can be employed for dyeing the entire head of hair and for highlighting or lightening only certain sections of the hair.
Thus, the objective of the present invention is to obtain novel compositions for oxidatively dyeing the hair. Another objective of the invention is to obtain hair coloring compositions that have a unique, non-drip consistency or rheology and yet spreads easily on the hair while imparting other advantages to the hair such as conditioning, a healthy appearance, shine and less damage to the hair.